Spin‐Active Polarons Induced Nucleophilic Substitution on Fluorographene for In Situ Fabricating Distinctively 2D‐Based Bifunctional Nanocomposites

Abstract Nucleophilic substitution reaction (S _N R) plays a crucial role in traditional organic chemistry, and its extension into two dimensional (2D) materials has recently created a series of functional materials and advanced applications. However, the traditional S _N R process is usually indiscriminately copied into existing 2D reaction systems, which tremendously restricts the development of special 2D functional materials and sophisticated applications. In this work, a brand‐new spin‐active polarons‐induced S _N R process in typical 2D fluorographene (FG) is proposed, where nucleophiles preferentially attack particular oxygen groups for functional grafting, simultaneously inducing the generation of spin‐active polarons and subsequently rapid defluorination on the FG nanosheet. It is further revealed that the polarons are moderate but ongoing at low temperature and robust but short‐lived at room temperature, respectively, no matter of the type of nucleophile. Finally, the particular spin‐active polarons are regulated to fabricate a distinctively bifunctional and high‐performance graphene‐based nanofluid and self‐sustained, moist‐electric energy harvesting hydrogel with high and stable power generation (≈0.75 V, 4.5 µA, 33.6 mW m ⁻² ) by an in situ polymerization‐nanocomposite strategy. This work explores a unique 2D reaction process to break through the traditional S _N R process on 2D materials, which offers a broad avenue to fabricate novel 2D‐based bifunctional materials and nanocomposites toward sophisticated applications.